Horizontal-cylinder piston.



N0. 818,860. PATENTED APR. 24, 1906. F.L.BATBS. HORIZONTAL CYLINDER PISTON.

APPLICATION FILED 0CT.12, 1905.

4. mnesses Ina/auto) WWW), 32 M 455 UNITED STATES FRANK L. BATES, OF SAN FRANCISCO, CALIFORNIA.

HORIZONTAL-CYLINDER PISTON.

Specification of Letters Patent.

Patented April 24, 1906.-

Application filed October 12, 1905. Serial No. 282,424.

To all whom it may concern:

Be it known that I, FRANK L. BATES, a citizen of the United States, residing in the city and county of San Francisco and State of California, have invented new and useful Improvements in Horizontal-Cylinder Pistons, of which the following is a specification.

My invention relates to improvements in pistons for engines in which the cylinder is of a horizontal type, and is designed to relieve injurious wear and pressure of the piston upon the bottom of the cylinder.

It consists in the combination of arts and in details of construction which wil be more fully explained by reference'to the accompanying drawings, in which- Figure 1 shows'the position of my iston in a cyhnder. Fig. 2 is a side view of t e piston looking from the left of Fig. 1. Fig. 3 is a bottom view of same.

In the construction of engines, pum s, and other machinery having horizontal ydisposed cylinders with pistons reciprocating therein it is customary to make the pistonhead of sufficiently smaller diameter than the interior of the cyllnder to prevent its binding therein, and especially when subjected to considerable heat, as in the case of hot gases or steam which may be used for propulsion. Such pistons have grooves cut in them and elastlc or snap rings, so called, fitting the grooves and expanded sufficiently to fill the bore of the cylinder to make a ti ht 'oint with the interior surface thereof. guc pistons, and especially of larger diameters, are heavy, and there is nothing to prevent the weight of the piston-head resting upon the bottom of the cylinder, thus causing a great deal of wear, which makes it necessaryin a comparatively short time to renew these wearing parts.

It is the object of my invention to so construct the piston as to relieve this wear and to prolong the life of the parts. Taking a 1000- motive-cylinder and its piston as representative of these parts, the piston-head may be as much as one-eighth of an inch less in diameter than the interior of the cylinder, and by reason of this difference in diameter the arc of curvature of the periphery of the piston will be different from that of the interior of the cylinder. Conse uently the weight of the piston resting upon t e bottom of the cylinder will rapidly wear the latter and soon destroy its shape, so that leaks will occur in spite of the rings, the curvature of which will not then fit the distorted shape of the cylinder.

In my invention the piston-head is turned so that the lower partsay for one-quarter of the circun1ferenceis made of the exact curvature of the interior of the cylinder, and the remainder of the head is turned down to a smaller diameter. A is such a piston, and the lower portion, extending from 2 to 3, represents that part which has a curvature substantially the same as the interior of the cylinder. The remainder of the curvature, extending over the top from 2 to 3, is made sufficiently smaller to provide the necessary clearance. Such a piston may be first turned to the smaller diameter, then the centers may be changed, and the small out which will be made upon the side correspondin with the longer radius of the new center wi I produce the enlarged circle whichis represented by the lower are 2 3. It will be understood that the reverse of this operation would effect the same result, the large curve being first time and the smaller curve afterward. By this construction the piston-head is evenly supported upon the bottom of the cylinder and the tendency to roll from side to side, which is present when the whole circumference of the piston is smaller than the interior of the cylinder, is to agreat extent avoided. In ad dition to this grooves 4 are cut around this lower portion of the cylinder and between the outer snap-rings 5 and the central ring 6, these rooves terminating at about the ends of the ar 'e curvature referred to in the lower part of the piston. Holes 7 are bored into the cylinder from each end and are connected with these grooves by vertically-intersecting passages, so that w en under pressure of steam or under compression when running without steam the pressure admitted through these 0 enings and into the channels will act to lift t e piston and in a manner support it upon a film of elastic fluid, which will in a great measure relieve it of the ressure upon the bottom of the cylinder. '1 e snap-rings 5 have the ends separated, so that by their elasticity these rings expand and make a sufficiently tight joint with the interior of the cylinder. The open ends of the. rings abut against stops at 8, located within the larger arc of the bottom of the piston-head, and as this portion of the head forms a perfect fit with the interior of the cylinder it prevents steam or fluid under pressure from entering the channels and expanding the rings against the interior of the cylinder with too great a frictional pressure.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s-

1. The combination with a cylinder, of a piston reciprocable therein, said piston havmg a segment forming the lower portion, with a radius of curvature normally the same as the interior of the cylinder, and the remainder of the circumference of a curvature normally upon a smaller radius.

2; A piston, a cylinder within which it is adapted to reciprocate, said piston normally having the upper and larger portion of its circumference with a smaller radius than that of the cylinder to provide clearance, and the remaining portion of the piston having a curvature normally upon the same radius as that of the interior of the cylinder.

3. A horizontal cylinder, a piston adapted to reciprocate therein, said piston being normally of smaller diameter than the interior of the cylinder for a portion of its circumference and having the remainder of the circumference normally with a curvature of the same radius as that of the interior of the cylinder and resting upon the bottom of the cylinder, snap-rings fitting grooves in the piston to form tight joints between it and the cyllnd er,

- shallow grooves extending parallel with and 4. A horizontal cylinder, a iston-reciprocable therein, said piston-head aving the upper and larger portionsjof its circumference normally with a 'smaller,radius than that of the cylinder and the remainin portion normally upon the same radius as t at of the cylinder-bore, snap-rin s fitting grooves in the piston, and having their separatei ends fixed within the space covered by the larger arc of the piston-head.

' In testimony whereof I have hereunto set my haul in presence of two subscribing Witnesses.

FRANK L. BATES.

Witnesses S. H. NoURsE, JAMES MASON. 

